Tanzanian Spinel Gems
When it comes to gemstones, natural spinel isn't particularly well-known, especially when it comes to commercial retail jewelry. In fact, for most of time, spinel was mistaken for other gems, such as varieties of corundum, like the curious case of 'The Black Prince's Ruby'. Spinel is highly prized for its excellent hardness (8 on Mohs scale), and compared to precious ruby, spinel has greater dispersion (fire) and brilliance. Spinel is also one of the few singly refractive gems, which gives it the ability to exhibit intense colors with a special level of purity. Best of all, spinel is never treated unlike sapphire and ruby, making it one of the best untreated gemstones on the market.

Historically, Burma (Myanmar) has been the world's primary source for fine quality spinel, which is also one of the reasons it has been a difficult gemstone to source for most buyers. However, since the last decade, spinel has become much more openly available because of Tanzanian deposits being commercialized. Burma is still the leader when it comes to the rare red spinel, but Tanzania is becoming one of the top producers for other attractive spinel colors, such as pink, violet, blue and unusual orange, as well as a bright purple variety too. Most spinel is very hard to find in gems weighing over 1 carat, but many spinel gems from Tanzania are being discovered in very large sizes, often weighing over 5-10 carats. Nowadays, in addition to Burma and Tanzania, spinel is also mined and sourced from Sri Lanka and Tajikistan, usually alongside ruby and sapphire.